Photographs showed the blue fishing boat rocking violently before capsizing, sending migrants tumbling into the sea. Some then climbed onto the hull of the overturned vessel, while others swam for life boats or toward the navy ship.

Women and children were among those rescued, but no details of the migrants' nationalities have been given.

The Italian navy patrol boat, Bettica, saw the vessel was in difficulty and approached it to hand out life jackets, but before it could begin a rescue the boat flipped over due to the sudden movement of the passengers.

Navy frigate Bergamini deployed a helicopter, and several rubber motor boats were used in the rescue operations.

Italy's coastguard said 5,600 migrants were rescued on Monday and Tuesday, and officials fear numbers will increase as weather conditions continue to improve.

In the past two years, more than 320,000 boat migrants have arrived on Italian shores and an estimated 7,000 died in the Mediterranean as they sought to reach Europe, according to the International Organisation for Migration.

Yesterday, Chancellor Angela Merkel's Cabinet approved a raft of new measures combining "opportunities and obligations" designed to help Germany deal with the influx of about 1.1 million asylum-seekers registered as entering the country last year, and help those who stay become "good neighbours and citizens".

The package seeks to provide migrants with better access to the German job market and also foresees the creation of some 100,000 government-funded 'job opportunities' for migrants. At the same time, migrants will be expected to participate in expanded orientation and language courses, which will also be made available more quickly and to more people than before.

Ms Merkel told reporters that Germany has "learned from the past" when immigrants were frequently thought of as guest workers or otherwise temporary residents and integration measures were not offered. Now that they are, "we expect people to take up these offers so that integration can work better," she said.